Electeical testing instrument



lE. G. BURE'SCH. ELECTRICAL TESTING INSTRUMENT.

APPLICATION FILED MAY I9, 1919. I 1,363,491. Patented Dee. 28,1920.

2 SHEETS-SHEET l.

E. G. BURESCH.

ELECTRICAL TESTING INSTRUMENT.

APPLICATION min' MAY 19. 1919.

Patented Dec. 28,1920.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE. .i

`EDWARD G. BURESCH, OF CHICAGO, ILLINOIS, ASSIGNOR OF ONE-HALF T0 OTTOJ'. BURESCH AND 0NE-HALF TO CHARLES A. BITZA, BOTH OF CHICAGO, ILLINOIS.

ELECTRICAL TESTING INSTRUMENT.

Specification of Letters Patent.

Patented Dec. 28, 1920.

Application filed May 19, 1919. Serial No. 298,173.

My present invention relates to improve-` ments in an electrical testinginstrument, and has special reference to the provision and arrangementof facilities for testing the various electrical elements which areembodied in and constitute the electrical equipment of automobiles.Electricity is now generally employed in automobiles for lighting andstarting, as well as ignition,

and to provide for this additional service a storage battery and agenerator are generally installed. All the elements employed inconnection with these divers uses are liable to get out of order and theseveral elements are not generally made by the same manufacturer so thatWhen anything in connection with the electricalequipment of anautomobile gets out of order it is very often a diiiicult matter,involving a visit to the rseveral different specialists in the variousparts evento find out what theftrouble is. One main object of myinvention is to provide in a handy and economical form a' single articlein which shall be associated the various instrumentalities for makingthe divers requisite tests. Another object of my invention is not onlyto provide facilities for finding out whether the various elements of anelectrical system are working, but also to ascertain whether theseelements are working as efficiently as they are designed to and shouldbe working. In attaining this latter object, I have provided a system ofcircuits to'which, or in which the suspected element can be connected orinserted Aand which will provide practicallyv ideal condiu tions foritsoperation instead of being compelled to test the element in the circuitin which the difficulty arose and which circuit may have a number ofunsuspected imperections which would embarrass the test.

Still other and further yobjects of my in.

vention are to simplify the testing equip ment for the respective testsboth for the f I attain the foregoing objects bymeans of the structureand arrangement of the parts illustrated in the accompanying drawings,in whichl Figure 1 is a iront elevation of an instruf ment boardprovided with the test devices and the means for making the necessaryelectrical 'connections 'for' performing the tests,

Fig. 2 is a rear elevation of the structure shown in Fig. 1; and,

Fig. 8 is a schematic view of the combination and arrangement ofelectric circuits employed. n

I have employed the sameiefeience characters `for designating the sameparts in the respective views. In 'carrying out my invention, I haveprovided an instrument-board 10, in the upper central portion whereof ismounted a combined ampere-meter 11 and voltmeter 12. To the left of thisinstrument and extending from the topto the bottom of the board, I haveprovided five horizontal rows oit' sockets from whichleads canconveniently be taken for making the. divers tests hereinafterdescribed.

There are four sockets in the first row which arenumbered,respectively,13, 111, 15 and 16. From sockets numbered 13 and 14 leads 13a and 14Caare taken to the posi- :tive and negative poles of a battery for thepurpose of ascertaining the voltage of the tors 13b and 11ib installedluponthe board and leading, respectively, to the poles 13c and 140 ofthe voltmeter 12. From the second two sockets 15 and 16 ofthe first rowleads are taken to any circuit for thepurpose of measuring the amperagethereof. From the two sockets 17 and 18 in the second row leads aretaken for the purpose of making low potential current tests for eithershorts, imperfect insulation, or broken Wires; the third row of threesockets 19,201and 21 are employed lor making connections for leads tothe low potential ends ofthe primary circuits of a coilto be tested, andto one of the high potential connections of the same coil in order toascertain if the spark delivered by this coil is up to its listed ratingor eiliciency. The tourth row of sockets 22, 23, 24 and 25 are employedfor taking leads for the purpose of testing spark plugs and also formaking tests with a high jviotential current for shorts in heavyinsulati such as the walls oi battery cells and eistributer cases. Thebottom row comprises two socleets, numbered. 26 and 27, respectively,,vhich are employed for taking leads to a battery or other dependablesource oi2 electricity i'or operating the circuits installed upon theboard.

Immediately below the combined voltmeter and an'ipere-meter are locatedcontact plates 28 and 29, respectively, which are emiloyed ior measuringthe capacity ot ruses lelow contact plates 28 and 29 mounted the base30, posts 3l and 32 and the adjustable rods 3B and 34k by means oit'which equipilicnt the sparking capacity and ciliciency of an inductionor vibrating coil may be tested, when it is desired to test theseelements independently of the circuit in which they were originallyinstalled.

immediately to the right oi"- the voltineter and ampere-meter arelocated tour switches, the iirst, number whereof contro s the maincircuit which supplies ciectri i y for the divers tests. The secondswitrn, number 36, controls the primary circuit Jfor the induction coilinstalled upon the baclr oit the board by means of which spart: plugsand spark producing equipment are tested. rlhe third switch, number 37,controls the circuit employed in testing the efliciency of induction Aorvibrating` coils, and the Afourth switch, number 3S, controls thecircuit 'for measuring the amperage oi lamps and for delivering acurrent of a known amperage. To the left oi the plates 2S and Q9 is ahunner or enunciator 39, and under the switches 35- to 38 inclusive, area group ot lamp socltets 40,

In order to make the various t sts independently of the system theelements of which are under investigation, start by leading wires .e ande directly as possible from the respective poles of a dependable sourceof current which may be the battery Z of the system under investigation,or any other battery or dependable source o'j current, rto the mainconnection sockets 26 and 27.

F or testing out any circuit or suspected portion of a circuit forimperfect insulation or for shorts or broken wires or otherimpertections leads are taken t'rom the soc iets 17 and 18 to theSuspected element. Sockets 27 and 17 are connected directly by the conductor a. Sockets 2G and 18 connected through the buzzer 14 by means ofthe con ductors and c through the switch 35. When the suspected portionor element oiI the system undery investigation is connected throughsuitable leads with sockets li' and 1S, the presence of a suspectedsnort will be indicated by the operation of the buzzer 39, anda-suspected broken wire will he equally :indicated by a failure of thebuzzer to operate. The conductors and c join through the switch which,as will be seen hereaiter, controls all o'f the circuits from thebattery sockets 26 and 2i' to the divers instruments.

For the purpose of measuring the capacity or the amperage oit the fuseused in connection with the lighting circuit, pro- ,i e the contactplates 2S and 29 spaced a suitable distance apart so that the usual *tein of fuse employed may conveniently be disposed between and in contactwith them. 'lhe plate 2S is connected with the conductor a through thebranch conductor d, while the plate 29 is connected by the conductor ewith one end oit a shunt-plate el and from there by means of a conductor,t to pole the ammeter or anrL ore-meter ll, the other pole ol' whichconnects by means of conductor g through the opposite end or theshunt-plate /ll and through a conductor la, with conductor c and thencethrough switch and conductor h to battery socket 26. lt will now be seenthat by closing the switch the amperage or capacity of the fuse injosedbetween the contact plates 2S and lay be measured.

have also provided the sockets or connections 'l5 and l@ which connectthrough the short branch conductors i and y' with the respective ends ofthe shunt-plate 921. The measurement oi any current within the limit ofthe shunt-plate and the ammeter may conveniently be made by directconnection et opposite ends oit the circuit to be tested so as tocomplete and close the circuit to be tested through the posts l5 and 1G.This connection is particularly useful in ascertai* ing whether thelighting circuit is e proper amount or too much current, and whether thegenerator is operating` up its rated eiiiciency. rlhe consumption ofelectricity by the primary circuit of a vibi yting coil may also bemeasured by connecting the low potential poles or the coil respectively'with the main battery socket @Y and the socket l5.

For measuring the consumption oi" one or more light bulbs independentlyet the circuits in which they are employed, and also iter securing acircuit of a known capacity for the regulated discharge of the storagebattery, which is sometimes desirable, l; pro vide the parallel stubconductors m and m connecting with the switch 38 by means of theconductor n and from the switch 38 to the conductor e by means of theconductor n', and also the parallel 'stub conductors 0 and 0 both ofwhich connect with the conductor l through the conductor g?. A suitablenumber, I have shown four, lamp socle ets L01 are interposed between andconnected with the conductor m and the conductor o, and an equal numberot lamp sockets 4101 also are interposed between and connected with thebranch conductors m and 0. It will now be seen that by closing switch 38a circuit will be closed through any of the sockets 40a or 40b which maycontain bulbs and the ammeter 11, and that the amperage of a light bulbinserted in any of the sockets will show on the ammeter. The amperage oflamp bulbs being fairly dependable a current of an amperage of anymultiple of the amperage of a single light bulb may be obtained byinserting the requisite number of light bulbs in the sockets 40a and401.

For the purpose of testing the efliciency of spark plugs independentlyof the ignition socket 22 of the fourth series of sockets.

The second socket 23 of the fourth series of sockets is connectedthrough the branch conductor r with the conductor c through which itcloses the circuit through the main battery socket 26. One of the highpotential posts 46 of the coil is connected through the conductor s withthe third socket 24 of the fourth series of sockets, and the highpotential circuit is closed by connection with the other high potentialpost 47 of the coil through the conductor s', and the conductors c and(l and short conductor s2 to the fourth socket 25. lVhen the centralsparking element of a plug is connecting with socket 24 by suitablewiring and the primary coil of the battery is closed by bridging sockets22 and 23 the induced high potential current will cause a sparking ofthe plug upon 'contacting the casing thereof with socket 25.

I have already indicated the connections to be made for testingsuspected shorts and suspected faulty insulation with the current as thesame is obtained from the storage battery or other primary source ofcurrent, but it is sometimes desirable in testing heavy insulation, suchas battery cell walls and distributer Walls, to use a high potential current in which case leads are taken from posts 24 and 25 to the sides ofthe suspected insulation so that this insulation will be subjected tothe potential or E. M. F. of the high potential currents. When this testis being made, I close the primary circuit of coil 42 through the switch36 by the conduc tors t and t leading, respectively, from opposite sidesof the switch to sockets 22 and 23, respectively.

It is sometimes found that the proper intensity of spark is not beingsecured even when the primary winding of the coil 1s apparently allright and consuming no more current than it should. In order to test thecapacity of a sparking coil to deliver a spark of the size for which itis rated independently of the circuit breaking instrumentalities of theautomobile, I have mounted upon the instrument-board, as heretoforedescribed, a suitable insulating base 30, posts 31 and y32 which aretransversely bored for the reception of the rods 33 and 34, the pointsof which may be adjusted With relation to each other so as to provide agap of the dimensions called for in the rating of the coil under test.

The primary poles 48 and 48a of the coil X to be tested arethenconnected with leads r and r ruiming from sockets 19 and 20, re-yspectively. Socket 19 is connected by conductor r2 with conductor t andthence to battery socket 26. Socket 20 is connected through switch 37 byconductors lw and rw with conductor r and then through the primary ofcoil 42 to battery socket 27. The high potential secondary pole 49 ofthe coil under test is then connected by means of the lead m with thepost 32 carrying the sparking point 34, and the high potential post 5()is connected by the lead w with the socket 21 which is connected throughthe circuit interrupter 44 by means of the conductors y and y with thepost 31 of the sparking point The reason for connecting circuits of thecoil under test with the poles for the sparking gap Athrough the circuitinterrupter of the coil 42'is to reproduce as far as possible theconditions present in the automobile circuit which are produced by theinterru )tion of the current by the timing and distri uting device.

What I claim is y l. A circuit for a testing instrument for the elementsof electric systems for automobiles comprising a battery connection, aconductor branching therefrom to separate indicator elements, pairs ofsockets7 conductors leading from a member of each pair of sockets tosaid respective indicator elements, and a branched conductor, thebranches whereof lead from the other member of each pair of sockets to asecond battery connection whereby each of said circuits may be closed byconnections between said pairs of sockets.

2. A testing instrument for the elements of electric systems forautomobiles comprising a main battery connection, a branched conductorleading from said main battery connection to and connecting withseparate indicating elements, pairs of terminal connectors, conductorsleading from said indicating elements to members of said pairs ofterminal connectors, a branched conductor the branches whereof lead fromthe opposite members of said pairs of terminal connectors to asecondmain battery connection whereby connections are made through said pairsof terminal connectors for including the elements to be tested Withinthe circuits or said indicating elements.

3. An instrument for testing the elements of electric systems Yforautomobiles comprising an induction coil, an aniineter, a buzzer, spacedcontact platesg adjustable sparking points, and a group of lamp socketsconnected in multiple are, a main battery connection? a branchedconnnctor leading` therefrom to poles of the aitoi'einen tionedelements, conductors leading from the opposite poles of saidaforementioned elements to separate terminal connectors, terminalconnectors pairing with said last mentioned terminal connectors, and abranched conductor the branches whereoll lead from said last mentionedterminal connectors to a second main battery connection.

4. An instrument 'for testing the elements :noemer of electrical systemsfor automobiles coinjprieing electrical testing devices.,` a mainbattery connection, a conductor leading from said main batteryconnection and branching, respectively, to a pole of each of saidelectric l testing devices, a second mainv battery connection, a seriesof socket conneet-ors, a conductor leading roin the second niain lotteryconnection and branching` to certain oi said socket connectors, andconductors leading;v from the poles of said electrical testing devices'to other of said socket connections whereby circuits including,` saidelectrical testing devices may be closed by leads from pairs ot saidsocket connectors.

Signed at Chicago, county of Cook and State et Illinois, this 2nd dayo'j May, 1919.

EDVARD BUltlESlll-i. Vtfitnesses z FLORENCE h/IITCHELL, BnNJ. T.Boom-ionen.

